/* カラーパレット（nanoBananaデザイン参考） */
:root {
    --color-primary-green: #7FB069;      /* 柔らかな緑系（メインカラー） */
    --color-accent-orange: #F4A261;      /* 温かみのあるオレンジ系（アクセントカラー） */
    --color-background: #F8F9FA;        /* 背景色（薄いグレー） */
    --color-white: #FFFFFF;
    --color-text-dark: #2C3E50;        /* テキスト（ダークグレー） */
    --color-text-light: #6C757D;
    --color-error: #E74C3C;
    --color-border: #DEE2E6;
    --shadow-card: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-card-hover: 0 8px 12px rgba(0, 0, 0, 0.15);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, #E8F5E9 0%, #F1F8E9 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.login-container {
    width: 100%;
    max-width: 420px;
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-card {
    background: var(--color-white);
    border-radius: 16px;
    box-shadow: var(--shadow-card);
    padding: 40px 32px;
    transition: box-shadow 0.3s ease;
}

.login-card:hover {
    box-shadow: var(--shadow-card-hover);
}

.login-header {
    text-align: center;
    margin-bottom: 32px;
}

.login-header h1 {
    color: var(--color-primary-green);
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.login-header .subtitle {
    color: var(--color-text-light);
    font-size: 14px;
    font-weight: 400;
}

.login-form {
    width: 100%;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    color: var(--color-text-dark);
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    font-size: 16px;
    transition: all 0.3s ease;
    background: var(--color-white);
    color: var(--color-text-dark);
}

.form-group input:focus {
    outline: none;
    border-color: var(--color-primary-green);
    box-shadow: 0 0 0 3px rgba(127, 176, 105, 0.1);
}

.form-group input::placeholder {
    color: var(--color-text-light);
}

.error-message {
    background: #FFF5F5;
    color: var(--color-error);
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 14px;
    margin-bottom: 16px;
    border: 1px solid #FED7D7;
    display: none;
}

.error-message.show {
    display: block;
    animation: shake 0.3s ease;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

.login-button {
    width: 100%;
    padding: 14px 24px;
    background: var(--color-primary-green);
    color: var(--color-white);
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 8px;
}

.login-button:hover {
    background: #6FA055;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(127, 176, 105, 0.3);
}

.login-button:active {
    transform: translateY(0);
}

.login-button:disabled {
    background: var(--color-text-light);
    cursor: not-allowed;
    transform: none;
}

.login-button.loading {
    position: relative;
    color: transparent;
}

.login-button.loading::after {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    top: 50%;
    left: 50%;
    margin-left: -10px;
    margin-top: -10px;
    border: 3px solid var(--color-white);
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.login-footer {
    margin-top: 24px;
    text-align: center;
}

.forgot-password {
    color: var(--color-primary-green);
    font-size: 14px;
    text-decoration: none;
    transition: color 0.3s ease;
}

.forgot-password:hover {
    color: #6FA055;
    text-decoration: underline;
}

/* レスポンシブ対応 */
@media (max-width: 480px) {
    .login-card {
        padding: 32px 24px;
    }
    
    .login-header h1 {
        font-size: 28px;
    }
    
    .form-group input {
        font-size: 16px; /* iOSでズームを防ぐ */
    }
}